Smog-chamber Fourier-transform infrared (FTIR) techniques were used to study the kinetics and photochemistry of C2F5C(O)CF(CF3)(2) in 50-700 Torr of air at 296 K. Upper limits for the rate constants of reactions of Cl atoms, OH radicals, and ozone with C2F5C(O)CF(CF3)(2) were established: k(Cl) < 1.7 x 10(-19), k(OH) < 5 x 10(-16), and k(O3) < 4 x 10(-22) cm(3) molecule(-1) s(-1). The ultraviolet absorption spectrum Of C2F5C(O)CF(CF3)(2) has a maximum at 305 nm where sigma(e) = 6.8 x 10(-20) cm(2) molecule(-1). C2F5C(O)CF(CF3)(2) is removed from the atmosphere by photolysis, which occurs on a time scale of approximately 1-2 weeks. As a result of its short atmospheric lifetime, the global warming potential of C2F5C(O)CF(CF3)(2) is negligible.